The Supreme Court’s decision on the controversial Obamacare legislation is now expected on Thursday.

The decision will likely be announced shortly after 10 a.m.

Many analysts expected the Supreme Court’s health care decision to come down on Monday. Instead, other major decisions were announced, including a ruling which mostly shot down Arizona’s polarized SB 1070 immigration law, and one which extended the campaign finance ruling of Citizens United to states.

Both of those decisions are likely to be heavily debated, and may have a significant impact on the 2012 elections.

The Obamacare ruling, though, is seen as the big one, the grand finale in this Supreme Court session.

So we keep waiting, and the Court keeps stringing us all along in this wild ride.

Why Will Obamacare Be Decided On Thursday? PolicyMic Legal Expert Mark Kogan explains that the Court probably does not want to double-up big cases. The health care decision is also the most complicated and most contentious, and there are potentially many opinions, which have to be checked, re-checked, and made sure to be consistent with one another, etc.

There are lots of moving parts, so maximum time to make sure everything is right is critical.

The key issues before the Court are whether Congress can fund the program by imposing an individual mandate that fines citizens for not purchasing health insurance, and whether the court can rule against that provision without overturning the entire law.

Republicans have assailed the individual mandate, the “heart” of Obamacare, as the element most likely to undo the president’s health care law. The individual mandate outlines that it is required by law that citizens purchase their own health insurance.

As the Court will vote along liberal-conservative lines, Justice Anthony Kennedy will be the wild card. Kennedy’s “swing vote” is unpredictable and it’s anybody’s guess on how he will vote on Obamacare. If he votes against the ACA, it will be five Republican-appointed justices against the law, and four Democrat-appointed judges voting for, giving the appearance that politics played an issue in the decision.

A senior member of the Court will likely present the opinion.

Why Does Chief Justice Roberts Get to Give the Obamacare Opinion? Again, our Legal Expert Mr. Kogan explains: The way it works is the senior judge usually gets the right to choose an opinion if they want it, meaning if Kennedy is the most senior in the majority, he can choose it. Similarly, the Chief could flip and commandeer the opinion because he is automatically most senior. It may be Kagan's opinion for all we know. But conventional wisdom says one of the more seniors took it, especially if it’s upheld. If it’s reversed, it may be a more junior justice (like Thomas or Scalia).

Opinions are generally randomly assigned. If a senior judge chooses it, it’s because they can write an opinion that can win a majority. In other words, Roberts can also take it if the majority is going to win to narrow the decision.

So, for example, let’s say its 5-4. The 5 in the majority will either randomly assign it, or the most senior judge there can take it. Anyone can write dissents/ concurrences. But the majority has to be written in such a way as to get all 5 to sign on, at least for the conclusion. Let’s say Kennedy joins the liberals, Roberts can jump from the minority to the majority and take the opinion, to write it more narrowly.